After a board refresh, four digits are missing on both the player 2 and player 3 score displays, though those display boards themselves are fine.

Four digits missing on the player 2 and 3 displays: bad driver IC12 on the master display

Cause: The digit driver chip IC12 on the master display board, which feeds those digits to the other displays, had failed. Some scorched resistors nearby still measured correctly and were not the cause.

Checks

• Swap displays to confirm the fault is not on the player 2 and 3 boards.
• Trace the missing digit lines back to their driver on the master display board.

Fix

• Replace IC12 on the master display board.

Score displays run on high voltage: unplug the game and let it discharge before touching the display boards.

Systems

• Williams System 3

Games

• Hot Tip

Related tips

• A segment missing on a score display
• Master display board versions
• All score displays dead
• UDN display driver chips
• One score display dead
• Whole digits missing
• Which UDN6184 drives which display
• Using a logic probe on the display board safely

Source: Pinball Repair help group!! (Facebook group)